Processes for improved performance of downstream oil conversion

ABSTRACT

The present technology provides processes for improving the performance of downstream oil conversion. Thus it provides, among others, processes for improving the yield of liquid hydrocarbons from a thermal conversion process. The processes include contacting a hydrocarbon feedstock with an effective amount of sodium metal and an effective amount of exogenous capping agent at a temperature of 250-500° C., to produce a mixture of sodium salts and a converted feedstock. The hydrocarbon feedstock may comprise hydrocarbons with a sulfur content of at least 0.5 wt %, an asphaltene content of at least 1 wt % and micro carbon residue content of at least 5 wt %. The converted feedstock may comprise hydrocarbons with a sulfur content less than that in the hydrocarbon feedstock, a micro carbon residue content less than that in the hydrocarbon feedstock and an asphaltene content less than that in the hydrocarbon feedstock. The process further comprises subjecting the converted feedstock to a thermal conversion process to produce a gaseous product, a purified product and a residual product, wherein the proportion of purified product to residual product is greater than that produced by subjecting the hydrocarbon feedstock in the same thermal conversion process.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional ApplicationNo. 63/027,052 filed on May 19, 2020, the contents of which areincorporated herein in their entirety.

FIELD OF THE TECHNOLOGY

The present technology relates to processes for reducing sulfur andasphaltene content in hydrocarbon feedstocks as well as other impuritiesto improve performance of downstream oil conversion processes. Bothcatalytic and thermal conversion performance may be improved.

BACKGROUND OF THE TECHNOLOGY

Hydrocarbon oils, including many oil feedstocks, often containdifficult-to-remove impurities such as sulfur in the form oforganosulfur compounds as well as metals and other heteroatom-containingcompounds that hinder usage of the hydrocarbons. The undesiredimpurities present in hydrocarbon oils can be concentrated in the resinsand asphaltenes found in the vacuum residue distillation fraction,generally defined by a boiling point of 510° C. to 565° C. (950° F. to1050° F.) or greater. Traditional refining configurations furtherconcentrate the undesired impurities by separating the high value, lowboiling point distillation fractions (gasoline, diesel, jet, andgasoils) from the low value, high boiling point bottoms fractions(atmospheric and vacuum residues). The low boiling point distillationfractions can be easily treated and converted into finished productsusing established processes such as hydrotreating, alkylation, catalyticreforming, catalytic cracking and the like. High boiling point residuumstreams cannot be easily treated because the disproportionately highmetals content fouls catalysts and the polyaromatic structure of theasphaltenes hinders access to impurities.

The sulfur species present in hydrocarbons can be characterized asasphaltenic sulfur (i.e., sulfur-containing asphaltene species) andnon-asphaltenic sulfur (i.e., sulfur-containing non-asphaltene species).Non-asphaltenic sulfur typically includes thiols, sulfides,benzothiophene and dibenzothiophene (DBT) derivatives among others, isprimarily located in the vacuum residuum fraction, but may also bepresent in the saturates, aromatics and resin components located in anydistillation fraction. These sulfur species, especially those locatedwithin the gasoline, naphtha, kerosene, diesel, and gasoil fractions,can generally be removed using conventional catalytic treatment orconversion processes such as hydrotreating, hydrodesulfurization orhydrocracking. Asphaltenic sulfur, located in the asphaltenes within theheaviest residuum distillation fraction, is primarily characterized bylayers of condensed, sulfur-containing polynuclear aromatic compoundslinked by saturated species and sulfur. DBT and DBT derivatives andsulfur bridges may account for a large proportion of the asphaltenicsulfur species. Additionally, metals, including nickel, vanadium andiron, are often concentrated within porphyrin metal complexes located inthe asphaltene fraction. Sulfur cannot be easily removed fromasphaltenes without subjecting the asphaltenic sulfur to severeoperating conditions.

Residuum thermal or catalytic conversion units operate under severeoperating conditions, typically high temperatures (>350° C./662° F.),high hydrogen partial pressures (500-3000 psig) and with specializedcatalysts that are deactivated by metals and coke deposition. Even aftersubjecting the residuum streams to the most severe operating conditions,a fraction of sulfur and metals is not removed and remains in the oil.As a result, low value residuum bottoms streams are either 1) convertedinto asphalt, 2) processed in a thermal conversion unit (like a coker)to extract as many high value intermediates as possible or 3) blendedinto high sulfur bunker fuel.

BRIEF SUMMARY OF THE TECHNOLOGY

Surprisingly, processes for preferentially removing the sulfur andmetals from sulfur-containing asphaltenes and/or converting a portion ofthe asphaltene fraction in hydrocarbon feedstocks into non-asphalteneliquid products have been discovered. The processes provide a convertedfeedstock with a reduced sulfur (and other heteroatom) content and areduced metals content, especially within the asphaltene fraction. Usingthe present technology, impurities concentrated in an asphaltenefraction of a hydrocarbon feedstock may be best removed by contactingsuch feeds with sodium metal while impurities concentrated elsewhere maybe best removed by traditional refining processes. Furthermore, theoperation of downstream process units may be optimized by reducing thehigh concentration of impurities within the asphaltene fraction,resulting in improved refinery operability and profitability.

Thus, in a first aspect, the present technology provides a process forimproving the yield of liquid hydrocarbons from a thermal conversionprocess comprising: contacting a hydrocarbon feedstock with an effectiveamount of sodium metal and an effective amount of exogenous cappingagent at a temperature of 250-500° C., to produce a mixture of sodiumsalts and a converted feedstock, wherein the hydrocarbon feedstockcomprises hydrocarbons with a sulfur content of at least 0.5 wt %, anasphaltene content of at least 1 wt % and micro carbon residue contentof at least 5 wt %; the converted feedstock comprises hydrocarbons witha sulfur content less than that in the hydrocarbon feedstock, a microcarbon residue content less than that in the hydrocarbon feedstockand/or an asphaltene content less than that in the hydrocarbonfeedstock; and subjecting the converted feedstock to a thermalconversion process to produce a gaseous product, a purified product anda residual product, wherein the proportion of purified product toresidual product is greater than that produced by subjecting thehydrocarbon feedstock to the same thermal conversion process. Inembodiments where the thermal conversion process is, e.g., a cokingprocess, the present process provides improved yield of vacuum gasoil,reduced coke losses, and lowers sulfur content of all subsequentstreams. The lower sulfur content translates into less H₂S to be handledby, e.g., a Claus plant, lower loads for gasoil hydrotreaters andsweeter coke. Moreover, the amount of sodium metal used in the processcan be varied to optimize downstream yields and economics.

In a second aspect, the present technology provides a process forpreparing anode grade coke from dirtier feeds than previously possible.The process comprises: contacting a hydrocarbon feedstock with aneffective amount of sodium metal and an effective amount of exogenouscapping agent at a temperature of 250-500° C., to produce a mixture ofsodium salts and a converted feedstock, wherein the hydrocarbonfeedstock comprises hydrocarbons with a sulfur content of at least 0.5wt %, an asphaltene content of at least 1 wt %, a vanadium content of atleast 15 ppm and a micro carbon residue content of at least 5 wt %; theconverted feedstock comprises hydrocarbons with a sulfur content lessthan that in the hydrocarbon feedstock, micro carbon residue less thanthat in the hydrocarbon feedstock and/or an asphaltene content less thanthat in the hydrocarbon feedstock; and subjecting the convertedfeedstock to a thermal conversion process to produce a premium anodegrade coke product with less than 0.5% wt % sulfur and less than 150 ppmvanadium.

In a third aspect, the present technology provides a process forpreparing needle grade coke from dirtier feeds than previously possible.The process comprises: contacting a hydrocarbon feedstock with aneffective amount of sodium metal and an effective amount of exogenouscapping agent at a temperature of 250° C.-500° C., to produce a mixtureof sodium salts and a converted feedstock, wherein the hydrocarbonfeedstock comprises hydrocarbons with a sulfur content of at least 0.5wt %, an asphaltene content of at least 1 wt %, a nickel content of atleast 10 ppm and a micro carbon residue content of at least 5 wt %; theconverted feedstock comprises hydrocarbons with a sulfur content lessthan that in the hydrocarbon feedstock, micro carbon residue less thanthat in the hydrocarbon feedstock and/or an asphaltene content less thanthat in the hydrocarbon feedstock; and subjecting the convertedfeedstock to a thermal conversion process to produce a high purityneedle coke product with less than 0.5 wt % sulfur, less than 0.7 wt %nitrogen, less than 10 ppm nickel, a coefficient of thermal expansiongreater than 2.5×10⁷/° C. and an electrical resistivity of 320×10⁶Ohm-In.

In a fourth aspect, the present technology provides a process forimproving the conversion of a hydrocarbon feedstock in catalyticconversion processes. The process comprises: combining a hydrocarbonfeedstock with an effective amount of sodium metal and an effectiveamount of exogenous capping agent at a temperature of 250° C.-500° C.,to produce a mixture of sodium salts and a converted feedstock, whereinthe hydrocarbon feedstock comprises hydrocarbons with a sulfur contentof at least 0.5 wt %, an asphaltene content of at least 1 wt % and atotal metal content of at least 100 ppm; the converted feedstockcomprises a hydrocarbon having a sulfur content less than 0.5 wt %, avanadium content less than 50 ppm, a nickel content less than 50 ppm, alower concentration of asphaltenes than that in the hydrocarbonfeedstock, and/or a greater proportion of lower boiling pointhydrocarbons (<538° C.) to residual hydrocarbons (>538° C.) than that inthe hydrocarbon feedstock; optionally subjecting the converted feedstockto a thermal conversion process to provide a double-converted product;and subjecting the converted feedstock or double-converted feedstock toa catalytic conversion process (e.g., catalytic hydroprocessing) toproduce a fuel grade product without blending or further conversionprocessing. This process improves conversion and performance ofhydrocarbon feeds, including residual streams, in downstream catalyticprocessing by a) improving catalyst life, b) providing higher gasolineyield, and c) allowing the coker to be bypassed completely.

In a fifth aspect, the present technology provides a process forproducing a low sulfur fuel-grade product from an out-of-specificationhydrocarbon feedstock with little or no blending. The process comprises:combining a hydrocarbon feedstock with an effective amount of sodiummetal and an effective amount of exogenous capping agent at atemperature of 250° C.-500° C., to produce a mixture of sodium salts anda converted feedstock, wherein the hydrocarbon feedstock compriseshydrocarbons with a sulfur content of at least 0.5 wt %, an asphaltenecontent of at least 1 wt % and fails to meet one or more fuel-gradespecifications selected from the group consisting of viscosity, density,micro carbon residue, metals content and cleanliness/compatibility; theconverted product comprises a hydrocarbon having a sulfur content lessthan 0.5 wt %, and meets one or more fuel grade specifications selectedfrom the group consisting of viscosity, density, micro carbon residue,metals content and compatibility; and the fuel-grade specifications areviscosity of less than 380 cSt @ 50 C, a density of less than 991 kg/m³,a micro carbon residue content less than 18 wt %, a vanadium contentless than 350 mg/kg and a cleanliness spot test result of 1 or 2 asmeasured by ASTM D4740. For example, low sulfur bunker fuel may beprepared via the disclosed method. In some embodiments, the product is anear fuel grade product that may be brought up to specification byblending a nominal amount of blendstock, e.g., blending 0.5 wt %-10 wt%.

The foregoing is a summary of the disclosure and thus by necessitycontains simplifications, generalizations, and omissions of detail.Consequently, those skilled in the art will appreciate that the summaryis illustrative only and is not intended to be in any way limiting.Other aspects, features, and advantages of the processes describedherein, as defined by the claims, will become apparent in the detaileddescription set forth herein and taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the manner in which the above-recited and other featuresand advantages of the technology are obtained will be readilyunderstood, a more particular description of the technology brieflydescribed above will be rendered by reference to specific embodimentsthereof that are illustrated in the appended drawings. Understandingthat these drawings depict only typical embodiments of the technologyand are not therefore to be considered to be limiting of its scope, thetechnology will be described and explained with additional specificityand detail through the use of the accompanying drawings in which:

FIG. 1 is a flow diagram of an illustrative embodiment of a first,second, or third aspect of a process of the present technology,including optional separation and electrolysis steps.

FIG. 2 is a flow diagram of an illustrative embodiment of a fourthaspect of a process of the present technology, including optionalseparation and electrolysis steps.

FIG. 3 is a flow diagram of another illustrative embodiment of a fourthaspect of a process of the present technology, including optionalseparation and electrolysis steps.

FIG. 4 is a flow diagram of an illustrative embodiment of a process ofthe present technology including optional pretreatment steps, andoptional separation and electrolysis steps, and a refinery processingstep.

DETAILED DESCRIPTION OF THE TECHNOLOGY

The following terms are used throughout as defined below.

As used herein, singular articles such as “a” and “an” and “the” andsimilar referents in the context of describing the elements (especiallyin the context of the following claims) are to be construed to coverboth the singular and the plural, unless otherwise indicated herein orclearly contradicted by context. Recitation of ranges of values hereinare merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the embodimentsand does not pose a limitation on the scope of the claims unlessotherwise stated. No language in the specification should be construedas indicating any non-claimed element as essential.

As used herein, “about” will be understood by persons of ordinary skillin the art and will vary to some extent depending upon the context inwhich it is used. If there are uses of the term which are not clear topersons of ordinary skill in the art, given the context in which it isused, “about” will mean up to plus or minus 10% of the particular term.

As used herein, “asphaltenes” refers to the constituents of oil that areinsoluble in any of the C₃₋₈ alkanes. Asphaltenes include polyaromaticmolecules that comprise one or more heteroatoms selected from S, N, andO. Sulfur species found in asphaltenes are collectively referred toherein as “asphaltenic sulfur.” All other sulfur species found in thenon-asphaltenic fractions of hydrocarbon oils and fractions thereof, arecollectively referred to herein as “non-asphaltenic sulfur.” The lattermay include, e.g., thiols, sulfates, thiophenes, includingbenzothiophenes and dibenzothiophenes, hydrogen sulfide and othersulfides.

As used herein, “hydrocarbon feedstocks” refers to any material that maybe an input for refining, conversion or other industrial process inwhich hydrocarbons are the principal constituents. Hydrocarbonfeedstocks may be solid or liquid at room temperature and may includenon-hydrocarbon constituents such as heteroatom-containing (e.g., S, N,O, P, metals) organic and inorganic materials. Crude oils, refinerystreams, chemical plant streams (e.g. steam cracked tar) and recyclingplant streams (e.g., lube oils and pyrolysis oil from tires or municipalsolid waste) are non-limiting examples of hydrocarbon feedstocks.

The present technology provides processes for improving the yield ofdownstream oil conversion processes. Thus, in a first aspect is provideda process for improving the yield of liquid hydrocarbons from a thermalconversion process comprising: contacting a hydrocarbon feedstock withan effective amount of sodium metal and an effective amount of exogenouscapping agent at a temperature of 250-500° C., to produce a mixture ofsodium salts and a converted feedstock. The hydrocarbon feedstockcomprises hydrocarbons with a sulfur content of at least 0.5 wt %, anasphaltene content of at least 1 wt % and micro carbon residue contentof at least 5 wt %. The converted feedstock comprises hydrocarbons witha sulfur content less than that in the hydrocarbon feedstock, a microcarbon residue content less than that in the hydrocarbon feedstockand/or an asphaltene content less than that in the hydrocarbonfeedstock. Micro carbon residue (MCR), measured according to ASTM D4530,indicates the tendency of a hydrocarbon to form carbonaceous depositsafter exposure to high temperatures. MCR is numerically equivalent tothe Conradson carbon residue (CCR), measured according to ASTM D189, andmay be used interchangeably. In any embodiments, the converted feedstockcomprises hydrocarbons with a sulfur content less than that in thehydrocarbon feedstock, a micro carbon residue content less than that inthe hydrocarbon feedstock and an asphaltene content less than that inthe hydrocarbon feedstock. The converted feedstock is subjected to athermal conversion process (e.g., a coking or visbreaking process) toproduce a gaseous product (e.g., steam, H₂S, C₁-C₄ saturated gases,C₂-C₄ olefins and isobutane), a purified product (e.g., naphtha, diesel,gasoils and light and heavy cycle oils) and a residual product (e.g.,coke or visbreaker tar), wherein the proportion of purified product toresidual product is greater than that produced by subjecting thehydrocarbon feedstock to the same thermal conversion process.

In a second aspect, a process for producing premium anode grade coke orneedle coke is provided. The process includes contacting a hydrocarbonfeedstock with an effective amount of sodium metal and an effectiveamount of exogenous capping agent at a temperature of 250-500° C., toproduce a mixture of sodium salts and a converted feedstock. Thehydrocarbon feedstock comprises hydrocarbons with a sulfur content of atleast 0.5 wt %, an asphaltene content of at least 1 wt %, a vanadiumcontent of at least 15 ppm and a micro carbon residue content of atleast 5 wt %. The converted feedstock comprises hydrocarbons with asulfur content less than that in the hydrocarbon feedstock, micro carbonresidue less than that in the hydrocarbon feedstock and/or an asphaltenecontent less than that in the hydrocarbon feedstock. In any embodiments,the converted feedstock comprises hydrocarbons with a sulfur contentless than that in the hydrocarbon feedstock, micro carbon residue lessthan that in the hydrocarbon feedstock and an asphaltene content lessthan that in the hydrocarbon feedstock. The converted feedstock issubjected to a thermal conversion process to produce a premium anodegrade coke product with less than 0.5% wt % sulfur and less than 150 ppmvanadium.

In a third aspect, there is provided a process for producing needlecoke, comprising contacting a hydrocarbon feedstock with an effectiveamount of sodium metal and an effective amount of exogenous cappingagent at a temperature of 250° C.-500° C., to produce a mixture ofsodium salts and a converted feedstock. The hydrocarbon feedstockcomprises hydrocarbons with a sulfur content of at least 0.5 wt %, anasphaltene content of at least 1 wt %, a nickel content of at least 10ppm and a micro carbon residue content of at least 5 wt %; the convertedfeedstock comprises hydrocarbons with a sulfur content less than 0.5 wt%, micro carbon residue less than that in the hydrocarbon feedstock, anasphaltene content less than 0.25 wt % and/or ash content <0.1 wt %. Inany embodiments, the converted feedstock comprises hydrocarbons with asulfur content less than 0.5 wt %, micro carbon residue less than thatin the hydrocarbon feedstock, an asphaltene content less than 0.25 wt%/o and ash content <0.1 wt %. The converted feedstock is treated in athermal conversion process to produce a high purity needle coke productwith less than 0.5 wt % sulfur, less than 0.7 wt % nitrogen, less than10 ppm nickel, a coefficient of thermal expansion greater than 2.5×10⁷/°C. and an electrical resistivity of 320×10⁶ Ohm-In.

In a fourth aspect, the present technology provides processes forimproving the conversion of feedstocks in a catalytic conversion or atreatment process. The process may include: combining a hydrocarbonfeedstock with an effective amount of sodium metal and an effectiveamount of exogenous capping agent at a temperature of 250° C.-500° C.,to produce a mixture of sodium salts and a converted feedstock;optionally further subjecting the converted feedstock to a thermalconversion process to provide a double-converted product; and subjectingthe converted feedstock or double-converted feedstock to a catalyticconversion process (e.g., catalytic hydroprocessing, fluid catalyticcracking, etc.) to produce a fuel grade product without blending orfurther conversion processing. In this process, the hydrocarbonfeedstock comprises hydrocarbons with a sulfur content of at least 0.5wt %, an asphaltene content of at least 1 wt % and a total metal contentof at least 100 ppm. The converted feedstock comprises a hydrocarbonhaving a sulfur content less than 0.5 wt %, a vanadium content less than50 ppm, a nickel content less than 50 ppm, a lower concentration ofasphaltenes than that in the hydrocarbon feedstock, and/or a greaterproportion of lower boiling point hydrocarbons (<538° C.) to residualhydrocarbons (>538° C.) than that in the hydrocarbon feedstock. In anyembodiments, the converted feedstock comprises a hydrocarbon having asulfur content less than 0.5 wt %, a vanadium content less than 50 ppm,a nickel content less than 50 ppm, a lower concentration of asphaltenesthan that in the hydrocarbon feedstock, and a greater proportion oflower boiling point hydrocarbons (<538° C.) to residual hydrocarbons(>538° C.) than that in the hydrocarbon feedstock.

In the fourth aspect, when the converted feedstock has a micro carbonresidue content of at least 5 wt %, the process may further includesubjecting the converted feedstock to a thermal conversion process(e.g., in a coker) to provide the double-converted feedstock and a solidcoke product. In such embodiments, the double-converted productcomprises a liquid hydrocarbon having a lower concentration ofimpurities than that in the hydrocarbon feedstock, and a proportion oflower boiling point hydrocarbons (<538° C.) to higher boiling pointresiduum hydrocarbons (>538° C.) greater than that of the convertedfeedstock. In any embodiments of the fourth aspect, the fuel gradeproduct may be gasoline, diesel, kerosene, jet fuel, petroleum naphtha,or LPG.

In a fifth aspect, the present technology provides processes forproducing low sulfur fuel-grade products. The processes includecombining a hydrocarbon feedstock with an effective amount of sodiummetal and an effective amount of exogenous capping agent at atemperature of 250° C.-500° C., to produce a mixture of sodium salts anda converted feedstock. The hydrocarbon feedstock comprises hydrocarbonswith a sulfur content of at least 0.5 wt %, an asphaltene content of atleast 1 wt % and fails to meet one or more fuel-grade specificationsselected from the group consisting of viscosity, density, micro carbonresidue, metals content and cleanliness/compatibility. The convertedproduct comprises a hydrocarbon having a sulfur content less than 0.5 wt%, and meets one or more fuel grade specifications selected from thegroup consisting of viscosity, density, micro carbon residue, metalscontent and compatibility, wherein the fuel-grade specifications areviscosity of less than 380 cSt @ 50 C, a density of less than 991 kg/m³,a micro carbon residue content less than 18 wt %, a vanadium contentless than 350 mg/kg and a cleanliness spot test result of 1 or 2 asmeasured by ASTM D4740. In some embodiments, the converted product meetstwo or more, three or more, four or more or all five fuel gradespecifications. In some embodiments, the product is a near fuel gradeproduct that may be brought up to specification by blending a nominalamount of blendstock, e.g., blending 0.5 wt %, 1 wt %, 2 wt %, 3 wt %, 4wt %, 5 wt %, 6 wt %, 7 wt %, 8 wt %, 9 wt %, or 10 wt %, or a rangebetween and including any two of the foregoing values such as 0.5-10 wt%, 1-10 wt % or 2-7 wt %.

In any embodiments of the processes described herein, the processes mayfurther include pretreating the hydrocarbon feedstock before thecontacting step to provide a purified feedstock and a pretreatedhydrocarbon feedstock. The purified feedstock comprises a lowerconcentration of impurities than the hydrocarbon feedstock beforepretreatment, the pretreated hydrocarbon feedstock comprises a higherconcentration of impurities than the purified feedstock; and thepretreated hydrocarbon feedstock is the feedstock subjected to thecontacting step to produce the converted feedstock. In any embodimentsof the present processes including a pretreating step, the pretreatmentstep may include phase separation by an externally applied field,separation by addition of heat, hydroconversion, thermal conversion,catalytic conversion or treatment, solvent extraction, solventdeasphalting or a combination of any two or more thereof. In anyembodiments, the pretreatment step may include contacting thehydrocarbon feedstock with exogenous hydrogen and/or a catalyst toremove one or more of sulfur, nitrogen, oxygen, metals and asphaltenes.Examples of pretreatment steps to produce a purified feedstock and apretreated hydrocarbon feedstock include atmospheric distillation,vacuum distillation, steam cracking, catalytic cracking, thermalcracking, fluid catalytic cracking (FCC), solvent deasphalting,hydrodesulfurization, visbreaking, pyrolysis, catalytic reforming,alkylation, and combinations of any two or more of the foregoing. Itwill be understood that certain of the foregoing processes, such asatmospheric distillation and vacuum distillation directly yield apurified feedstock and a pretreated hydrocarbon feedstock, while othersrequire a subsequent separation step. For example, steam cracking,catalytic cracking, thermal cracking, FCC and pyrolysis yield a mixtureof products that can be subsequently separated into a purified feedstockand a pretreated hydrocarbon feedstock by distillation or otherseparation process.

In any aspects or embodiments of the processes described hereinincluding a thermal conversion process, the thermal conversion processmay be or include visbreaking, delayed coking, fluid coking,Flexicoking™, pyrolysis, a variant thereof or a combination of any twoor more thereof. In any embodiments, the thermal conversion process maybe operated at a temperature about 400° C. to about 570° C. In anyembodiments, the thermal conversion process may be operated at apressure of about 10 to about 200 psig. In any embodiments, the thermalconversion process may be operated at about 450° C. to about 500° C. andat about 20-100 psig, e.g., as in a coker.

In any aspects or embodiments of the processes described hereinincluding a catalytic conversion process, the catalytic conversionprocess comprises fluid catalytic cracking (FCC), residual FCC,hydrotreating, residual hydrotreating, hydrocracking, catalyticreforming, hydrodesulfurization, hydrodenitrogenation,hydrodemetallation, or residue upgrading/hydroconversion (e.g., ARDS®,LC-Fining®, H-Oil®), their variants or a combination of any two or morethereof. The catalyst may comprise cobalt, molybdenum, nickel, tungsten,platinum, palladium, alumina, silica, zeolites, their isomers, oxides,sulfides or combinations of any two or more thereof. In any embodiments,the catalytic conversion process may be operated at a temperature fromabout 250° C. to about 575° C. In any embodiments, the catalyticconversion process may be operated at a pressure of about 10 to about3000 psig. In any embodiments, the catalytic conversion process may beoperated at about 400° C. to about 575° C. and at about 1000 to about3000 psig. In any embodiments, the catalytic conversion process may beoperated at about 450° C. to about 575° C. and at about 15 to about 100psig.

In any aspects or embodiments of the processes described herein, it willbe understood that other refinery processes such as distillation (bothatmospheric or vacuum distillation) may be employed as part of theprocess. Alternatively, in certain aspects or embodiments, otherrefinery processes may be used in place of thermal or catalyticconversion processes (see, e.g., FIG. 4 ).

Hydrocarbon feedstocks for the present processes are or may be derivedfrom virgin crude oils (for example petroleum, heavy oil, bitumen, shaleoil and oil shale). Hydrocarbon feedstocks may also be a residualfeedstock, e.g., the product of a thermal cracking process. Residualfeedstocks may be produced by various pretreatment processes of thepresent technology and will be referred to as “pretreated hydrocarbonfeedstocks,” which may also be contacted with sodium metal and exogenouscapping agent. Thus, pretreated feedstocks may include distillationproducts of hydrocarbon feedstocks, (atmospheric or vacuum residuums,gasoline, diesel, kerosene, and gas oils), and refinery intermediatestreams. In any embodiments, the pretreated hydrocarbon feedstock mayinclude hydrotreated products, hydrocracker residue, hydroconversionresidue (e.g., LC-Finer® (Chevron Global Lummus) residue, or H-Oil®(Axens) residue), FCC slurry, residual FCC slurry, atmospheric or vacuumresiduums, solvent deasphalting tar, deasphalted oil, steam cracked tar,visbreaker tar, high sulfur fuel oil, low sulfur fuel oil, asphaltenes,asphalt and coke. The foregoing hydrocarbon feedstocks (includingpretreated hydrocarbon feedstocks) may be derived from any geologicalformation (oil sand, conventional or tight reservoirs, shale oil, oilshale) or geographical location (North America, South America, MiddleEast, etc.). In certain aspects and embodiments of the presentprocesses, especially the second and third aspects, the hydrocarbonfeedstock includes a significant amount of aromatic compounds, e.g., atleast 10 wt %, at least 20 wt %, at least 25 wt %, at least 30 wt %,

In processes of the present technology, the hydrocarbon feedstockincludes hydrocarbons (e.g., a hydrocarbon oil) and impurities.Similarly, the residual feedstock includes hydrocarbons and impurities.In some embodiments, the residual feedstock has a higher concentrationof impurities than the hydrocarbon feedstock. “Impurities” as usedherein refer to heteroatoms (i.e., atoms other than carbon andhydrogen), such as sulfur, oxygen, nitrogen, phosphorous, and metals.Impurities may be found in or include substances such as naphthenicacids, water, ammonia, hydrogen sulfide, thiols, thiophenes,benzothiophenes, porphyrins, Fe, V, Ni, and the like. In any embodimentsof the present processes, the hydrocarbon feedstock or residualfeedstock includes hydrocarbons with a sulfur content of at least 0.5 wt% and an asphaltene content of at least 1 wt %. The sulfur contentcomprises asphaltenic sulfur and non-asphaltenic sulfur, but is measuredas the wt % of sulfur atoms in the feedstock. In any embodiments, thesulfur content may range from 0.5 wt % to 15 wt %, including forexample, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 7, 8, 9, 10, 11, 12,13, 14, or 15 wt % or a range between and including any two of theforegoing values. Thus, the sulfur content may range may be, in anyembodiments, 1 wt % to 15 wt %, 0.5 wt % to 8 wt %, or 1.5 wt % to 10 wt%.

In processes of the present technology, the asphaltene content refers tothe total amount of asphaltenes in a feedstock measured as the n-pentaneinsoluble fraction of the feedstock. However, in some aspects orembodiments of the present processes, the asphaltene content may bemeasured as the insoluble fraction precipitated or otherwise separatedfrom the feedstock, after mixing with a sufficient quantity of one ormore C₃₋₈ alkanes. The C₃₋₈ alkanes may be propane, butane, pentane,hexane, heptane, octane, isomers thereof, or mixtures of any two or morethereof. In any embodiments, the asphaltene content of a feed may bedefined as the constituents insoluble in heptane. A detailed discussionof the physical properties and structure of asphaltenes and the processconditions (temperatures, pressures, solvent/oil ratios) required toproduce a specific asphaltene is described in J. G. Speight, “PetroleumAsphaltenes Part 1: Asphaltenes, Resins and the Structure of Petroleum”,Oil & Gas Science and Technology—Rev IFP, Vol 59 (2004) pp. 467-477(incorporated herein by reference in its entirety and for all purposes).The standard test method for determining heptane (C7) insolubleasphaltene content is described by ASTM standard D6560-17 and can beextended to any alkane, including pentane.

In any embodiments of the present processes, the asphaltene content ofhydrocarbon feedstock or residual feedstock may be at least 1 wt %, atleast 2 wt %, at least 3 wt %, at least 4 wt % or at least 5 wt %. Forexample, the asphaltene content may range from 1 wt % to 100 wt %, suchas 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55,60, 70, 80, 90, 95 or 100 wt % or between and including any two of theforegoing values. Thus, in any embodiments, the asphaltene content mayrange from 2 wt % to 100 wt %, 1 wt % to 30 wt %, 2 wt % to 30 wt %, 5wt % to 100 wt %, 10 wt % to 100 wt %, or 20 wt % to 100 wt %.

In any embodiments of the present process, it may be necessary to dilutethe hydrocarbon feedstock with a diluent if an elevated asphaltenecontent in the hydrocarbon feedstock leads to a viscosity that is toohigh for the sodium treatment process. Because of the aromatic nature ofasphaltenes, a diluent will typically include aromatics (i.e., compoundshaving aromatic rings). The diluent may be a single compound (e.g.,benzene, toluene, xylene, ethylbenzene, cumene, naphthalene,1-methylnaphthalene), mixtures of any two or more thereof, or a refineryintermediate that is aromatic (e.g., light cycle oil, reformate). Theamount of diluent needed will vary with the asphaltene content of thefeedstock and the viscosity required for processing. Higher asphaltenecontent in a feedstock may require more diluent than a feedstock withlower asphaltene content. It is within the skill in the art to select anappropriate amount of diluent to permit processing of asphaltenes in thepresent processes.

The present processes may also reduce/remove the naphthenic acid contentand/or the metals content in converted feedstocks compared to thehydrocarbon and pretreated hydrocarbon feedstocks. In any embodimentsthe hydrocarbon feedstock or pretreated hydrocarbon feedstock includes(on an aggregate or individual basis) about 1 to about 10,000 ppmmetals. The metals may be naturally occurring metals bound to thehydrocarbon structure or residual metal fragments entrained in thepretreated hydrocarbon feedstock during upstream processing (e.g.,corrosion products or catalyst fragments). In any embodiments, the metalis selected from the group consisting alkali metals, alkali earthmetals, transition metals, post transition metals, and metalloids havingan atomic weight equal to or less than 82. In any embodiments, the metalis selected from the group of vanadium, nickel, iron, arsenic, lead,cadmium, copper, zinc, chromium, molybdenum, silicon, calcium,potassium, aluminum, magnesium, manganese, titanium, mercury andcombinations of any two or more thereof. In any embodiments, the metalis selected from the group consisting of vanadium, nickel, iron, andcombinations of any two or more thereof. In any embodiments, the metalsconcentration of the hydrocarbon feedstock or the pretreated hydrocarbonfeedstock may be (in the aggregate or on an individual basis) about 2 toabout 10,000 ppm, about 10 to about 10,000 ppm, about 100 to about10,000 ppm, about 100 to about 5,000 ppm, about 10 to about 1,000 ppm,about 100 to about 1,000 ppm, and the like.

The processes of the present technology not only upgrade the hydrocarbonand pretreated hydrocarbon feedstocks employed by removal/reduction ofimpurities, but may also improve physical properties such as viscosityand density. The hydrocarbon feedstock or pretreated hydrocarbonfeedstock may have a viscosity between 1 to 10,000,000 cSt at 50° C. Forexample, the viscosity may 1, 10, 25, 50, 100, 200, 300, 400, 500,1,000, 2,000, 5,000, 10,000, 25,000, 50,000, 100,000, 500,000,1,000,000, 2,000,000, 3,000,000, 4,000,000, 5,000,000, 6,000,000,7,000,000, 8,000,000, or 9,000,000 cSt or a range between and includingany two of the foregoing values. Thus, in any embodiments, the viscosityof the hydrocarbon feedstock or the pretreated hydrocarbon feedstock maybe, e.g., 100 to 10,000,000 cSt, 380 to 9,000,000 cSt, 500 to 9,000,000cSt, or 500 to 5,000,000 cSt, among others.

The hydrocarbon feedstock or pretreated hydrocarbon feedstock may adensity from 800 to 1200 kg/m³ at 15.6° C. or 60° F. For example, thedensity may be 800, 825, 850, 875, 900, 925, 975, 1000, 1050, 1100,1150, or 1200 kg/m³ or a range between and including any two of theforegoing values. Thus, in any embodiments, the density may be, e.g.,from 850 to 1200 kg/m³, 900 to 1200 kg/m³, 950 to 1200 kg/m³, or 925 to1100 kg/m³.

In processes of the present technology, the hydrocarbon feedstock orpretreated hydrocarbon feedstock is contacted with an effective amountof sodium metal and an effective amount of exogenous capping agent. Anysuitable source of sodium metal may be used, including, but not limitedto electrochemically generated sodium metal, e.g., as described in U.S.Pat. No. 8,088,270, incorporated by reference in its entirety herein. By“effective amount” is meant the amount of a material or agent to bringabout a desired consequence. For example, an effective amount of sodiummetal in the present processes may include a stoichiometric,suprastoichiometric or substochiometric amount of sodium metalsufficient to reduce the amount of asphaltene and/or sulfur in thehydrocarbon feedstock.

The exogenous capping agent used in the present processes is typicallyused to cap the radicals formed when sulfur and other heteroatoms havebeen abstracted by the sodium metal during the contacting step. Althoughsome feedstocks may inherently contain small amounts of naturallyoccurring capping agents (“endogenous capping agents”), such amounts areinsufficient to cap substantially all of the free radicals generated bythe present processes. Effective amounts of exogenous (i.e., added)capping agents are used in the present processes, such as 1-1.5 moles ofcapping agent (e.g., hydrogen) may be used per mole of sulfur, nitrogen,or oxygen present. It is within the skill of the art to determine aneffective amount of exogenous capping agent needed to carry out thepresent processes for the particular hydrocarbon feedstock or pretreatedhydrocarbon feedstock being used based on the disclosure herein. Theexogenous capping agent may include hydrogen, hydrogen sulfide, naturalgas, methane, ethane, propane, butane, pentane, ethene, propene, butene,pentene, dienes, isomers of the forgoing, or a mixture of any two ormore thereof. In any embodiments, the exogenous capping agent may behydrogen and/or a C₁₋₆ acyclic alkanes and/or C₂₋₆ acyclic alkene or amixture of any two or more thereof.

The effective amount of sodium in its metallic state and used in thecontacting step will vary with the level of heteroatom, metal, andasphaltene impurities of the hydrocarbon and pretreated hydrocarbonfeedstocks, the desired extent of conversion or removal of an impurity,the temperature used and other conditions. In any embodiments,stoichiometric or greater than stoichiometric amounts of sodium metalmay be used to remove all or nearly all sulfur content, e.g., 1-3 moleequivalents of sodium metal versus sulfur content. In any embodiments,the hydrocarbon feedstock or pretreated hydrocarbon feedstock iscontacted with more than 1 mole equivalent of sodium metal versus thesulfur content therein, e.g., 1.1, 1.15, 1.2, 1.25, 1.3, 1.4, 1.5, 2,2.5 or 3 mole equivalents of sodium metal.

Surprisingly, a sub-stoichiometric ratio of metallic sodium to sulfurcontent (in the hydrocarbon/pretreated hydrocarbon feedstocks) may beused to preferentially lower the amount of asphaltenic sulfur versus thenon-asphaltenic sulfur. Thus, in any embodiments, the pretreatedhydrocarbon feedstock (or alternatively the hydrocarbon feedstock) maybe contacted with a less than stoichiometric amount of sodium metal tothe sulfur content therein. In the present technology, it will beunderstood that the stoichiometric amount of sodium metal to sulfurcontent is the theoretical amount of sodium metal required to convertall sulfur content in the pretreated hydrocarbon (or hydrocarbon)feedstock to sodium sulfide. For example, it will be appreciated bythose of skill in the art that the stoichiometric amount of sodium metalnecessary to convert all of the sulfur to sodium sulfide in a feedstockcontaining about 1 mole of sulfur atoms is 2 moles of sodium metal. Aless than stoichiometric amount of sodium metal to sulfur content insuch an example would be less than 2 moles of sodium metal, such as 1.6moles, or 0.8 mole equivalents of sodium metal. In any embodiments, theless than stoichiometric amount of sodium metal to sulfur content may be0.1 equivalents to less than 1 equivalent. Examples of suchsub-stoichiometric amounts include 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7,0.8, 0.9 or less than 1 equivalents of sodium metal to sulfur content ora range between and including any two of the foregoing values. Thus, inany embodiments the sub-stoichiometric amounts may range from 0.1 to 0.9equivalents, 0.2 to 0.8 equivalents, 0.4 to 0.8 equivalents, or thelike.

As the contacting step takes place at a temperature of about 250° C. toabout 500° C., the sodium metal will be in a molten (i.e., liquid)state. For example the contacting step may be carried out at about 250°C., about 275° C., about 300° C., about 325° C., about 350° C., about375° C., about 400° C., about 425° C., about 450° C., about 500° C., ora range between and including any two of the foregoing temperatures.Thus, in any embodiments the contacting may take place at about 275° C.to about 425° C., or about 300° C. to about 400° C. (e.g., at about 350°C.).

In any embodiments, the contacting step may take place at a pressure ofabout 400 to about 3000 psi, e.g., at about 400 psi, about 500 psi,about 600 psi, about 750 psi, about 1000 psi, about 1250 psi, about 1500psi, about 2000 psi, about 2500 psi, about 3000 psi or a range betweenand including any two of the foregoing values.

The reaction of sodium metal with heteroatom contaminants in thehydrocarbon/pretreated hydrocarbon feedstocks is relatively fast, beingcomplete within a few minutes, if not seconds. Mixing the combination offeedstock and metallic sodium further speeds the reaction and iscommonly used for this reaction on the industrial scale. However,certain embodiments may require an extended residence time to improvethe extent of conversion or adjust the operating conditions to targetremoval of a specific heteroatom impurity. Hence, in any embodiments thecontacting step is carried out for about 1 minute to about 120 minutes,e.g., about 1, about 5, about 7, about 9, about 10, about 15 minutes,about 30, about 45 about 60, about 75, about 90, about 105, or about 120minutes, or is conducted for a time ranging between and including anytwo of the foregoing values. Thus, in any embodiments the time may rangefrom about 1 to about 60 minutes, about 5 minutes to about 60 minutes,about 1 to about 15 minutes, about 60 minutes to 120 minutes, or thelike.

The present processes produce a converted feedstock that include ahydrocarbon oil with a sulfur content less than that in the hydrocarbonfeedstock (or pretreated hydrocarbon feedstock). In any embodiments, thesulfur content of the converted feedstock may be less than 0.5 wt %,e.g., less than or about 0.4 wt %, less than or about 0.3 wt %, lessthan or about 0.2 wt %, less than or about 0.1 wt %, and even less thanor about 0.05 wt %, or a range between and including any two of theforegoing values. Removal efficiency of the sulfur content (a.k.a.,conversion efficiency) from the hydrocarbon or pretreated hydrocarbonfeedstock compared to the converted feedstock may be at least 40%, atleast 50%, at least 60%, at least 70%, at least 80%, at least 90%, atleast 95%, at least 96%, at least 97%, at least 98%, at least 99% or100% by weight, or a range between and including any two of theforegoing values. Where the effective amount of sodium metal is greaterthan a stoichiometric amount, the sulfur content conversion efficiencycan be very high, e.g., at least 90%.

When sub-stoichiometric amounts of sodium metal are used in the presentprocesses (including but not limited to processes of the first, second,third and fourth aspects), lower conversion efficiencies are observed,but the sulfur content from asphaltenic sulfur is preferentially reducedcompared to that from non-asphaltenic sulfur. For example, the (total)sulfur content conversion efficiency may range from about 10% to about80%, including, about 10%, about 20%, about 30%, about 40%, about 50%,about 60%, about 70%, about 80%, or a range between and including anytwo of the foregoing values. At the same time, the corresponding sulfurcontent conversion efficiency of asphaltenic sulfur is higher at eachpoint than the total sulfur-conversion efficiency. For example sulfurcontent conversion efficiency of asphaltenic sulfur for any given feedmay range from 1% to 40% higher (e.g., 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%,9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 22%, 24%,25%, 27%, 30%, 32%, 35%, 37%, or 40% higher or a range between andincluding any two of the foregoing values) than the correspondingoverall sulfur content conversion efficiency.

The converted feedstocks of the present technology have a reducedconcentration of metals compared to the hydrocarbon or pretreatedhydrocarbon feedstocks. The metals content of the converted feedstockmay be reduced by at least 20% compared to the hydrocarbon feedstock orpretreated hydrocarbon feedstock, for example, by 20% to 100%. Examplesof the percent reduction in metals (collectively or individually) in theconverted feedstock compared to the hydrocarbon feedstock or thepretreated hydrocarbon feedstock include 20%, 30%, 40%, 50%, 60%, 70%,80%, 90%, 95%, 97%, 98%, 99%, 100%, or a range between and including anytwo or more of the foregoing values. Thus, in any embodiments thepercent reduction may be from 20% to 99%, from 20% to 95%, from 70% to99% or to 100%. The metals may be any of those disclosed herein. In someembodiments, the metals are selected from iron, vanadium, nickel orcombinations of any two or more thereof. For example, the iron andvanadium content of the converted feedstock has been reduced by at least20% compared to the hydrocarbon feedstock or pretreated hydrocarbonfeedstock. Similarly, in any embodiments, the nickel content of theconverted feedstock has been reduced by at least 20% compared to thehydrocarbon feedstock or pretreated hydrocarbon feedstock.

The present processes also provide converted feedstocks with improvedphysical properties compared to the hydrocarbon feedstock or pretreatedhydrocarbon feedstock. However, it has been discovered that the physicalproperties of converted feedstocks of the present processes do notnecessarily change proportionately to the sodium to sulfur ratio. Forexample, the extent of metals demetallization, especially metalsdetrimental to catalyst life including iron, vanadium and nickel willgenerally be greater than the extent of desulfurization for a givensodium to sulfur ratio. Example 6 demonstrates the insensitivity ofsodium treatment to initial metals content, unlike catalytic conversionprocesses. Sodium demetallization at low sodium/total sulfur additionratio could be highly advantageous for pre-treating a hydrocarbon feedwith an undesirably high metals content prior to catalytic conversion ortreatment.

Additional physical properties that greatly reduce the value of heavyresidual feedstocks are improved after treatment with sodium.Desulfurization of the asphaltene fraction occurs without the hydrogensaturation observed in hydroconversion or the carbon rejection exhibitedby thermal cracking processes. As a result, at least a portion of theasphaltene content is converted by the present processes into a soluble,stable and desulfurized converted liquid product, increasing the yieldof higher value liquid products (e.g., hydrocarbon oils derived fromasphaltenes. Thus, the converted feedstock produced by the presentprocesses may have an asphaltene content less than that in thehydrocarbon feedstock (or pretreated hydrocarbon feedstock). In anyembodiments, the present processes convert at least some asphaltenes toa hydrocarbon oil, such as paraffins. In any embodiments, at least 5%,at least 10%, at least 15%, at least 20% or more of the asphaltenecontent in the pretreated hydrocarbon feedstock is converted to a liquidhydrocarbon oil in the converted feedstock. Conversion efficiency forthe asphaltene content removed from the hydrocarbon or pretreatedhydrocarbon feedstocks varies with the amount of sodium used, but isgenerally high, e.g., at least 70%, at least 75%, at least 80%, at least85%, at least 90%, at least 95%, up to 98%, up to 99% or even up to99.9% or 100%, or a range between and including any two of the foregoingvalues (e.g., 70% to 100%, or 75% to 99.9%, etc.).

The conversion of asphaltenes to smaller, lower molecular weightcomponents with fewer attached functional groups typically results in areduction in viscosity of at least 40% to as much as 5 orders ofmagnitude (10000×) and an increase in the API gravity by about 1 toabout 3 units for each wt % sulfur removed. In any embodiments, theviscosity of the converted feedstock may be reduced by at least 50 cStat 50° C. or by at least 40%. In any such embodiments, the viscosity isreduced at 50° C. by at least 100 cSt, at least 200 cSt, at least 300cSt, or more. For any of the hydrocarbon feedstocks or pretreatedhydrocarbon feedstocks disclosed herein with viscosities above 1,000 cSt(see above), the reductions are particularly great and may be at least50%, at least 60%, at least 70%, at least 80%, at least 90%, at least95%, at least 99%, or even 100% (e.g., at least a 40 to 99% reduction inviscosity. In any embodiments, the density of the converted feedstock isdecreased by about 5 to about 25 kg/m³ per wt % reduction in sulfurcontent of the converted feedstock compared to the hydrocarbon feedstockor pretreated hydrocarbon feedstock. For example, the decrease indensity may be about 5, about 10, about 15, about 20, about 25 kg/m³ ora range between and including any two of the foregoing values (such asabout 5 to about 20 kg/m³ or about 10 to about 25 kg/m³, etc.).

As noted above, in any embodiments, the present processes may includepretreating a hydrocarbon feedstock containing impurities prior tocontacting with sodium metal. In some cases, a hydrocarbon feedstock maybe pretreated to concentrate the impurities in the pretreatedhydrocarbon feedstock and therefore reduce the volume of feedstock toprocess. For example, a virgin crude oil may be distilled to produce oneor more light distillate cuts as the purified feedstock and anatmospheric residuum (the pretreated hydrocarbon feedstock) with ahigher sulfur content and higher asphaltene content than that in boththe purified feedstock and the virgin crude (hydrocarbon feedstock).Alternatively, a hydrocarbon feedstock may be pre-treated to remove aportion of the undesired impurities to provide for a purified feedstockwith a lower concentration of impurities and a pretreated hydrocarbonfeedstock with impurities that remain after pre-treatment. Thepretreated hydrocarbon feedstock may comprise impurities because of thechosen level of conversion or because the pre-treatment process cannotremove the impurity. For example, a vacuum residuum may be treated in ahydroprocessing reactor (such as an LC-Fining® unit or H-Oil® unit) toremove sulfur and convert the residuum fraction to higher valueproducts. However, after hydroprocessing at operating conditionsexceeding 350 C and 1500-3000 psig in the presence of catalysts, arecalcitrant sulfur and asphaltene fraction remains in thehydroprocessed bottoms stream. The pre-treatment process may comprise aseparation process, a thermal or catalytic conversion process or atreatment process, or combinations of any two or more thereof.

In any embodiments, the pretreatment process may include a separationprocess that comprises one or more of a physical separation using energy(heat), phase addition (solvent or absorbent), a change in pressure, orapplication of an external field or gradient to concentrate the impurityin the pretreated hydrocarbon feedstock. The separation process mayinclude gravity separation, flash vaporization, distillation,condensation, drying, liquid-liquid extraction, stripping, absorption,centrifugation, electrostatic separation and their variants. Theseparation process may further comprise solvent extraction processes,including solvent deasphalting processes, such as Residuum OilSupercritical Extraction (ROSE®). For example, a hydrocarbon feedstockmay be desalted to remove salt and water, an API separator may be usedto separate water and solids from oil or a distillation column may beused to separate low sulfur, low boiling point products from highsulfur, high boiling point products in crude oil. The separation processmay also require a solid agent or barrier, such as adsorption,filtration, osmosis or their variants. Each of the disclosed separationprocesses results in a purified feedstock with a lower concentration ofimpurities than the hydrocarbon feedstock and a pretreated hydrocarbonfeedstock with a higher concentration of impurities than the purifiedfeedstock. In any embodiments, the pretreated hydrocarbon feedstockcomprises impurities at a higher concentration than in the hydrocarbonfeedstock.

In any embodiments, the pretreatment process may include thermal orcatalytic processes that modifies the molecular structure or results inrejection of at least a portion of the carbon content of the hydrocarbonfeedstock. The thermal conversion process may include a coker, avisbreaker or other process to increase the yield of cracked distillatesby rejecting carbon as coke. The catalytic processes may include fixedbed and fluidized bed processes such as, but not limited to catalyticcrackers (FCC or Residuum FCC), hydrocrackers, residuum hydrocrackersand hydroconversion (e.g., LC Fining®, H-Oil®). The conversion processmay be a hydroprocessing process that requires both hydrogen andcatalysts.

The pretreatment step of the present processes may include a treatmentprocess that results in hydrocarbon saturation or removal of a specificimpurity on a whole feed basis. Thus, in any embodiments, thepretreating process may include solvent deasphalting, hydrotreating,residuum hydrotreating (RHT), hydrodesulfurization (RDS),hydrodemetallization (HDM) or hydrodenitrification (HDN) or acombination of two or more thereof. While the overall concentration ofan impurity (or impurities) may be reduced, treatment processesgenerally produce a purified feedstock with a lower concentration ofimpurities than the hydrocarbon feedstock and a pretreated hydrocarbonfeedstock with a higher concentration of impurities than the purifiedfeedstock. Nevertheless, the concentration of impurities in thepretreated hydrocarbon feedstock may be lower than the hydrocarbonfeedstock. Additionally, catalytic treatment processes cannot typicallyprocess feedstocks with high concentrations of impurities in asphaltenesbecause of accelerated catalyst deactivation from the metals andmicro-carbon residue.

Processes of the present technology produces a mixture that includes theconverted feedstock and sodium salts. The present processes may furtherinclude separating the sodium salts from the converted feedstock. Thesodium salts are comprised of particles, which can be quite fine (e.g.,<10 μm) and cannot be completely removed by standard separationtechniques (e.g., filtration or centrifugation). In any embodiments, theseparating may include a heating the mixture of sodium salts andconverted feedstock with elemental sulfur to a temperature from about150° C. to 500° C. to provide a sulfur-treated mixture comprisingagglomerated sodium salts; and separating the agglomerated sodium saltsfrom the sulfur treated mixture, to provide a desulfurized liquidhydrocarbon and separated sodium salts. This separation may be carriedout as described in U.S. Pat. No. 10,435,631, the entire contents ofwhich are incorporated by reference herein for all purposes.

The present processes may further include recovering metallic sodiumfrom the separated sodium salts. In any embodiments, the presentprocesses may further include electrolyzing the separated sodium saltsto provide sodium metal. The separated sodium salts may comprise one ormore of sodium sulfide, sodium hydrosulfide, or sodium polysulfide. Theelectrolyzing may be carried out in an electrochemical cell inaccordance with, e.g., U.S. Pat. No. 8,088,270, or U.S. ProvisionalPatent Application No. 62/985,287, the entire contents of each of whichare incorporated by reference herein for all purposes. Theelectrochemical cell may include an anolyte compartment, a catholytecompartment, and a NaSICON membrane that separates the anolytecompartment from the catholyte compartment. A cathode comprising sodiummetal is disposed in a catholyte in the catholyte compartment. An anodecomprising the sodium salts are disposed in anolyte in the anolytecompartment. An electrical power supply is electrically connected to theanode and cathode. In any embodiments, the separated sodium salts aredissolved in an organic solvent prior to electrolyzing the salts toprovide sodium metal.

Current thermal and catalytic desulfurization processes produce ahydrogen sulfide byproduct that must be treated in a sulfur recoveryunit such as a Claus plant. Sulfur recovery units (SRU) are veryefficient, but release sulfur emissions during operation; therefore,refining complexes are subject to stringent sulfur emission limits thatare regulated by local and national authorities. In many cases, refiningcomplexes operate near or at their sulfur emission limits.Desulfurization using sodium produces an elemental sulfur product thatcan be stored as a solid or liquid and sold to the market. Eachorganically bound sulfur removed using sodium displaces an equivalentamount of sulfur as H₂S that must be processed in the SRU. As a result,a refining complex gains operational flexibility to either reduce thethroughput and operating cost of (and resulting sulfur emissions from)the existing SRU or to increase the sulfur processing capacity of thefacility by desulfurizing at least a part of the hydrocarbon feedstockwith sodium. In any embodiments, the present processes include a sulfurrecovery step employing a sulfur recovery unit (e.g., Claus Plants, SCOTunits, or the like). In any such embodiments, the capacity of the sulfurrecovery unit is increased proportionately to the sulfur recoveredduring treatment of the hydrocarbon feedstock with sodium.

Illustrative embodiments of processes of the present technology will nowbe described with reference to the flow diagrams of FIGS. 1-4 . Withrespect to the purification and conversion system 10 of FIG. 1 , thehydrocarbon feedstock 101, containing sulfur and asphaltene impuritiesas described herein (e.g., a sulfur content of at least 0.5 wt %(herein, “wt %” means “weight percent”) and an asphaltene content of atleast 1 wt %), is charged to reactor 120 (continuous or batch) alongwith effective amounts of sodium metal 103 and an exogenous cappingagent 105 as described herein. The reaction may be carried out atelevated temperature and pressure as described herein and is typicallycomplete within minutes to give a mixture 121 of sodium salts andconverted feedstock, although higher asphaltene-containing feeds mayrequire longer times as disclosed herein. The converted feedstockincludes a hydrocarbon oil with a sulfur content less than that in thehydrocarbon feedstock and may include an asphaltene content less thanthat in the hydrocarbon feedstock as described herein. Additionally, theproportion of asphaltenic sulfur to non-asphaltenic sulfur in theconverted feedstock is lower than in the hydrocarbon feedstock.Optionally, the mixture 121 is transported from the reactor 120 toanother vessel 130 where the sodium salts are agglomerated to particleslarge enough to be easily separated from the converted feedstock.Although any suitable agglomeration method may be used, agglomerationwith elemental sulfur 107 at elevated temperature as described hereinmay be used. The resulting mixture 131 of agglomerated sodium salts,metals and converted feedstock may then be separated by any suitableprocess and device 140, such as by a centrifuge, to give the convertedfeedstock 141, free of metals 143 and sodium salts 145. Optionally, asdescribed herein, the sodium salts 145 may be subjected to electrolysisin an electrolytic cell 150 with a sodium ion-selective ceramic membrane152 such as a NaSiCON membrane to provide sodium metal 153 and elementalsulfur 157. The sodium metal 153 and elemental sulfur 157 may be reusedas 103 and 107, respectively, in the present process. The convertedfeedstock 141 may be subjected to a thermal conversion process, 160,e.g., a coking process, a visbreaking process, or other such processesas described herein, to provide a purified product 161 (e.g., naphtha,diesel, gasoils and light and heavy cycle oils), a gaseous product 163(e.g., steam, H₂S, C₁-C₄ saturated gases, C₂-C₄ olefins and isobutane),and a residual product 165 (e.g., coke or visbreaker tar). Theproportion of purified product 161 to residual product 165 is greaterthan that produced by subjecting the hydrocarbon feedstock 101 to thesame thermal conversion process without first desulfurizing the feedusing sodium as described herein.

In some embodiments of the present processes utilizing the purificationand conversion system 10 of FIG. 1 , the hydrocarbon feedstock 101comprises hydrocarbons with a sulfur content of at least 0.5 wt %, anasphaltene content of at least 1 wt %, a vanadium content of at least 15ppm and a micro carbon residue content of at least 5 wt %. The convertedfeedstock 121/141 comprises hydrocarbons with a sulfur content less thanthat in the hydrocarbon feedstock 101, micro carbon residue less thanthat in feedstock 101, and may contain an asphaltene content less thanthat in the hydrocarbon feedstock 101. After subjecting the convertedfeedstock 141 to a suitable thermal conversion process, a premium anodegrade coke may be produced with less than 0.5% wt % sulfur and less than150 ppm vanadium.

FIG. 2 illustrates another process embodiment of the present technologyusing the purification and conversion system 20. The impure hydrocarbonfeedstock 201 may include hydrocarbons with a sulfur content of at least0.5 wt %, an asphaltene content of at least 1 wt % and a total metalcontent of at least 100 ppm. This feedstock is charged to a reactor 220,along with sodium metal 203 and an exogenous capping agent 205,analogous to the process illustrated in FIG. 1 and as described herein.The resulting mixture 221 of sodium salts and converted feedstock may beprocessed to agglomerate 230 (with elemental sulfur 207) and separate240 the sodium salts 245 from the converted feedstock 241 as describedherein. The converted feedstock 241 includes hydrocarbons having asulfur content less than 0.5 wt %, a vanadium content less than 50 ppm,a nickel content less than 50 ppm, a lower concentration of asphaltenesthan that in the hydrocarbon feedstock, and/or a greater proportion oflower boiling point hydrocarbons (<538° C.) to residual hydrocarbons(>538° C.) than that in the hydrocarbon feedstock 201. Again, the sodiumsalts 245 may be electrolyzed 250 to provide sodium metal 253 andelemental sulfur 257 as described herein. The converted feedstock 241,is then subjected to a catalytic conversion process (such ashydrotreatment 270 using hydrogen 265), or other such processes asdescribed herein. Fuel grade products 272 are produced in this fashion.

Alternatively, as shown in FIG. 3 , the same process embodiment may becarried out using purification and conversion system 30, but employingan optional thermal conversion step 360 to produce a double convertedproduct 361, which is then subjected to a catalytic conversion process370 using hydrogen to again produce fuel grade products 372. Analogouslyto FIG. 2 , the thermal conversion process 360 also produces, gaseousproduct 363 and residual product 365.

FIG. 4 illustrates another process embodiment of the present technologyusing the purification and conversion system 40, wherein the impurehydrocarbon feedstock 401 is pretreated in a process/device 400 toprovide a first residual feedstock 402 and a purified feedstock 404. Anysuitable pretreatment process resulting in a first residual feedstock402 and a first purified feedstock 404 may be used as described herein.The residual feedstock 402 may optionally be further pretreated (410) toprovide a second residual feedstock 411 and a purified feedstock 413.Optionally, one or more impurities (e.g., gaseous impurities such asH₂S, NH₃, water, light hydrocarbons, etc.) may be removed in a separatestream 415 during the first and/or second (as shown) pretreatment step.The second residual feedstock 411 may then be treated with sodium metal403 and exogenous capping agent 405 in reactor 420 as described hereinto provide a mixture 421 of sodium salts and converted feedstock. Thesodium salts of mixture 421 may then be agglomerated (430) and separated(440) as described before to provide the converted feedstock 441, metals443, and sodium salts 445. The sodium salts 445 may be electrolyzed inan electrolytic cell 450 with a sodium ion-selective ceramic membrane452 (e.g., NaSiCON) as described herein to provide recovered sodiummetal 453 and elemental sulfur 457. The converted feedstock 441 may besubjected to any refinery process(es) 480 (e.g., distillation, thermalconversion, catalytic conversion, or the like) to give fuel gradeproducts 482 and a residual product 481.

EXAMPLES Example 1—De-Sulfurization of Hydrocarbon Feedstocks withSodium

A variety of hydrocarbon feedstocks were treated with sodium metal todemonstrate the wide applicability of sodium metal treatment forremoving impurities and improving physical properties. The hydrocarbonfeedstocks included virgin crude oils from different geographicallocations and geological formations, and a variety of converted andtreated feedstocks located within typical refining and upgradingfacilities, 700 g of the hydrocarbon feedstock was treated with anappropriate mass of sodium in a 1.8 L Parr continuously stirred tankreactor using a batch or semi-batch system under the followingconditions to yield a mixture of converted hydrocarbon and sodium salts.The reaction conditions, feed and product properties are shown in Table1.

The results from Table 1 clearly indicate that molten sodium metaleffectively removes impurities and improves the physical properties ofthe converted feedstock, therefore improving the fungibility of theconverted feedstock. The converted feedstock may now be sold directly asa fuel grade product or converted to higher value products in downstreamrefinery units rather than be sold as asphalt or high sulfur bunker fueloil.

TABLE 1 Alberta American Colombian Feedstock Bitumen VR VR ReactionConditions Temperature (C.) 350 350 357 Pressure (psig) 1500 750 1500Mole equivalents of sodium 1.15 1.35 1.34 Residence Time 60 60 60Physical Properties Feed Product Feed Product Feed Product Sulfur (wt %)4.50 0.50 3.40 0.03 3.90 0.01 API Gravity 8.3 17.8 1.2 4.3 5.8 13.3Density (kg/m3) 1012 948 1066 1042 1031 977 Viscosity @ 50 C. (cSt)2,871,000 568 4,714,000 284,000 432,000 706 Viscosity @ 80 C. (cSt)Resid Cut (524+ C.) 50% 35% 90.0% 83.0% 75.9% 52.3% C5 Asphaltenes (wt%) 14.1% 3.6% C7 Asphaltenes (wt %) 10.7%  1% 25.0% 16.0% 20.1% 13.9%MCRT (wt %) 35.0% 28.0% Vanadium (ppm) 146 17 515 3 Nickel (ppm) 63 21115 4 Iron (ppm) 56 13 Total Metals (ppm) 289 5 265 51 629 7 ConversionEfficiency Sulfur (wt %) 88.9% 99.1% 99.7% Total Metals (ppm) 98.3%80.8% 98.9% C5 Asphaltenes (wt %) 90.7% 36.0% 30.8% Product QualityImprovement Density (kg/m3 per wt % S removed) 16.10 7.22 13.72Viscosity Reduction @ 50 C. (cSt) 2,870,432 4,430,000 431,294 ViscosityReduction @ 50 C. (%) 100.0% 94.0% 99.8% Middle SDA Tar FeedstockEastern VR Blend Asphaltenes Reaction Conditions Temperature (C.) 358350 358 Pressure (psig) 1500 750 1500 Mole equivalents of sodium 1.131.12 1.07 Residence Time 60 60 60 Physical Properties Feed Product FeedProduct Feed Product Sulfur (wt %) 5.10 0.02 5.00 0.04 8.20 0.02 APIGravity 4.71 8.3 6.3 13.1 −11 13 Density (kg/m3) 1039 1012 1027 979 1174979 Viscosity @ 50 C. (cSt) 8,947,478 32,380 2,123 N/A Viscosity @ 80 C.(cSt) 690 Resid Cut (524+ C.) 92.3% 40.4% 70.0% 63.0% 90.5% 46.8% C5Asphaltenes (wt %) 23.3% 10.9% C7 Asphaltenes (wt %) 14.2% 4.8% 16.8%6.6% 64.9% MCRT (wt %) 28.3% 19.5% 12% Vanadium (ppm) 195 3 200 52 675 5Nickel (ppm) 53 4 64 21 201 18 Iron (ppm) 51 3 Total Metals (ppm) 252 7315 76 926 23 Conversion Efficiency Sulfur (wt %) 99.6% 99.2% 99.8%Total Metals (ppm) 97.2% 76.0% 97.5% C5 Asphaltenes (wt %) 66.3% 60.7%100.0% Product Quality Improvement Density (kg/m3 per wt % S removed)5.25 9.74 23.84 Viscosity Reduction @ 50 C. (cSt) 30,257 ViscosityReduction @ 50 C. (%) 93.4% Visbreaker Hydrocracker HydroconversionFeedstock Residue Residue Bottoms Reaction Conditions Temperature (C.)350 350 350 Pressure (psig) 750 750 750 Mole equivalents of sodium 1.341.35 1.35 Residence Time 60 60 60 Physical Properties Feed Product FeedProduct Feed Product Sulfur (wt %) 2.00 0.30 3.80 0.30 2.40 0.50 APIGravity 9.3 12.3 3.9 9.2 8.9 12.5 Density (kg/m3) 1005 984 1045 10061008 983 Viscosity @ 50 C. (cSt) 1,944 656 501,200 27,980 658 375Viscosity @ 80 C. (cSt) Resid Cut (524+ C.) 71.0% 66.0% 85.0% 75.0%39.0% 33.0% C5 Asphaltenes (wt %) C7 Asphaltenes (wt %) 11.0% 8.2% 17.0%11.0% 7.9% 5.6% MCRT (wt %) 18.0% 14.8% 26.1% 19.3% 13.3% 10.3% Vanadium(ppm) 40 7 192 50 140 45 Nickel (ppm) 41 11 115 40 67 24 Iron (ppm) 47 225 6 644 0 Total Metals (ppm) 128 21 332 96 3136 160 ConversionEfficiency Sulfur (wt %) 85.0% 92.1% 79.2% Total Metals (ppm) 84.0%71.1% 94.9% C5 Asphaltenes (wt %) 25.5% 35.3% 29.1% Product QualityImprovement Density (kg/m3 per wt % S removed) 12.33 11.25 13.26Viscosity Reduction @ 50 C. (cSt) 1,288 473,220 283 Viscosity Reduction@ 50 C. (%) 66.3% 94.4% 43.0%

Example 2—De-Sulfurization of Hydrocarbon Feedstocks with Sodium

A variety of hydrocarbon feedstocks and pretreated hydrocarbonfeedstocks were treated with sodium metal in a pilot plant using acontinuous system essentially as shown, e.g., in FIG. 4 to furtherdemonstrate the wide applicability of sodium metal treatment forremoving impurities and improving physical properties during continuousoperation. The hydrocarbon and pretreated hydrocarbon feedstocksincluded virgin crude oil, vacuum residuums and partially convertedfeedstocks produced within typical refining and upgrading facilities.Each feedstock was treated with an appropriate mass of sodium in a 12 Lcontinuously stirred tank reactor under the following conditions toyield a mixture of converted hydrocarbon and sodium salts. Hydrogen wasthe exogenous capping agent for all test campaigns. The reactionconditions, feed and product properties are shown in Table 2.

Similar to Example 1, the results from Table 2 clearly indicate thatmolten sodium metal effectively removes impurities and improves thephysical properties of the converted feedstock, therefore improving thefungibility of the converted feedstock. The converted feedstock may nowbe sold directly as a fuel grade product or converted to higher valueproducts in downstream refinery units rather than be sold as asphalt orhigh sulfur bunker fuel oil.

TABLE 2 Diluted Conventional Hydroconversion Reaction Conditions VacuumResidual Crude Oil Bitumen Vacuum Residual Bottoms Feed Oil Quantity(kg/hr) 65.7 65 67.1 50.5 45.1 Sodium flow rate (kg/hr) 2.1 3.65 5.692.6 1.69 Reaction Temperature (° C.) 380 360 370 360 360 Pressure (psig)732 749 700 749 750 Mole equivalents of sodium 1.24 1.24 1.29 1.24 1.24Reactor Residence Time (min) 4.6 4.5 4.3 6.5 6.7 Physical PropertiesFeed Product Feed Product Feed Product Feed Product Feed Product APIGravity 11.3 12.9 12.5 15.9 10.3 14.7 7.5 10.8 7.9 10.6 Density (kg/m3)991 980 983 960 998 968 1018 994 1015 996 Kinematic Viscosity (cSt @ 50°C.) 650 374 603 254 2,308 492 191,500 21,510 1,075 592 KinematicViscosity (cSt @ 80° C.) 111 72 105 56 293 91 7,120 1,400 137 91 Sulfur(wt %) 1.76 0.49 3.14 0.48 4.57 0.49 2.88 0.61 2.1 0.51 Iron (wppm) 9013 6 3 22 0 105 7 105 0 Nickel (wppm) 32 10 39 15 88 24 61 18 65 21Vanadium (wppm) 69 23 100 43 240 59 123 53 85 19 Total Metals (wppm) 323110 212 70 369 101 359 90 699 42 Product Quality Improvement FeedProduct Feed Product Feed Product Feed Product Feed Product Densityreduction (kg/m³ per wt % S 8.65 8.52 7.36 10.40 12.13 removed)Viscosity Reduction @ 50° C. (cSt) 275 350 1,816 169,990 483 ViscosityReduction @ 50° C. (%) 42.4% 58.0% 78.7% 88.8% 45.0%

Example 3: Preferential Removal of Sulfur in Asphaltene Fraction

A blended vacuum residuum stream was treated with an increasing molarequivalent of sodium in 5 separate experiments. 700 g of vacuum residuumwas contacted with sodium at 350° C. and 750 psig of hydrogen partialpressure. Key results are summarized in Table 3. The effect of treatmentwith sodium on preferential removal of sulfur from the asphaltenefraction is summarized by:

-   -   1. the fraction of total sulfur located in the asphaltenes was        reduced from 28.5% to 7.9% of the converted product at a sodium        to sulfur ratio of 0.94.    -   2 The proportion of asphaltenic sulfur vs non-asphaltenic sulfur        is reduced as a function of increasing moles equivalents of        sodium. The reduction in proportion demonstrates that a greater        proportion of sulfur has been removed from asphaltenic sulfur        than from non-asphaltenic sulfur at all practical sodium to        sulfur ratios—a critical result for unloading hydroprocessing        catalysts in downstream refining processes (e.g., in the process        shown in FIG. 2 ).

TABLE 3 Removal of Sulfur from various oil fractions Sodium to sulfurratio (mol equivalent of sodium) Feed 0.19 0.37 0.56 0.75 0.94 ProductOil Total Sulfur Content (wt % feed) 2.17% 1.92% 1.63% 1.31% 1.01% 0.70%Total Asphaltene content (wt % feed) 12.6% 11.10% 10.30% 9.85% 8.54%7.73% Asphaltenic sulfur content (wt % of 4.9% 3.85% 2.90% 2.12% 1.28%0.71% asphaltene faction) Extent of Desulfurization Overall (wt %) — 12%25% 40% 54% 68% non-Asphaltenic sulfur content (wt % of — 3.9% 14.3%29.1% 42.0% 58.8% initial non-asphaltenic sulfur content) Asphaltenicsulfur content (wt % of — 30.8% 51.6% 66.2% 82.3% 91.1% initialasphaltenic sulfur content) Ratio of asphaltenic sulfur to non- — 7.93.6 2.3 2.0 1.5 asphaltenic sulfur removed (wt/wt) Fraction of sulfur inconverted hydrocarbon 28.5% 22.3% 18.3% 15.9% 10.8% 7.9% as asphaltenicsulfur content (wt %) Proportion of asphaltenic sulfur to 0.40 0.29 0.220.19 0.12 0.09 non-asphaltenic sulfur (g/g)

Example 4: Improving the Conversion of Hydrocarbons in CatalyticConversion Processes by Pre-Treating with Sodium

Refinery intermediate streams (i.e., pretreated hydrocarbon feedstocks)were treated with various molar equivalents of sodium to demonstrate howthe choice of molar equivalent of sodium can be used to improve theconversion of hydrocarbons in downstream catalytic conversion processes,700 g of each refinery intermediate was treated with sodium at 350° C.and 750 psig or 400° C. and 1500 psig of hydrogen partial pressure. Keyresults are summarized in Table 4

Treatment of hydrocarbon feedstock with a sub-stoichiometric molarequivalent of sodium may be preferable for pre-treating FCC or ResiduumHydrotreater (RHT) feedstocks by preferentially removing the impuritiesthat foul catalysts: asphaltenic sulfur, metals and asphaltenes. Agreater proportion of sulfur was removed from the asphaltene fraction inall cases. Additionally, the fraction of metals removed exceeds thefraction of total sulfur removed, indicating that a low sodium/sulfuraddition ratio may be favorable to produce a partially converted productwith low metals and asphaltenic sulfur content for further processing indownstream refinery processes.

TABLE 4 Blended Vacuum Hydroconversion Hydroconversion HydroconversionFeedstock Residuum Residue Residue Residue Molar equivalent of Sodium0.20 0.20 0.65 1.08 Sulfur Removal Total Sulfur wt %  19%  17%  47%  70%Non-Asphaltene Sulfur wt %   7%  12%  40%  64% Asphaltene Sulfur wt % 36%  21%  66%  89% Metals Removal Iron wt % 100.0%  99.4% 98.0% 99.0%Nickel wt % 76.2% 39.0% 61.0% 76.0% Vanadium wt % 74.7% 85.3% 97.0%98.0% Asphaltene Conversion yield Feed Asphaltene fraction wt % 12.6%15.5% 15.1% 15.1% Product Asphaltene fraction wt %  9.8% 12.6% 12.2%12.8% Asphaltene Conversion wt % 22.1% 18.7% 19.2% 15.2%

Example 5: Producing On-Spec Low Sulfur Fuel Oil from a Vacuum ResiduumFeedstock

A vacuum residuum feedstock was treated with sodium metal in a pilotplant using a continuous system, e.g., as shown in FIG. 1 , todemonstrate the production of on-spec low sulfur fuel oil. The vacuumresiduum feedstock was treated with an appropriate mass of sodium in a12 L continuously stirred tank reactor under the following conditions toyield a mixture of converted hydrocarbon and sodium salts. Hydrogen wasthe exogenous capping agent for all test campaigns. The reactionconditions, feed and product properties are shown in Table 5.

The example clearly demonstrates that an on-spec low sulfur fuel oil canbe produced when a hydrocarbon feedstock is contacted with an effectiveamount of sodium and an effective amount of exogenous capping agent.

TABLE 5 Reaction Conditions Diluted Vacuum Residuum Feed Oil Quantity(kg/hr) 65.8 Sodium flow rate (kg/hr) 2.1 Reaction Temperature (° C.)378 Pressure (psig) 750 Mole equivalents of sodium 1.26 ReactorResidence Time (min) 4.6 Iso 8217 2010 RMG Physical Properties FeedProduct 380 Spec Sulfur (wt %) 1.76 0.47  0.5 Max Density (kg/m3) 991976 991 Max Kinematic Viscosity (cSt @ 50 C.) 650 354 380 Max AcidNumber, mg KOH/g 0 0  2.5 Max MCRT, wt % 13 10  18 Max CCAI 838 870 MaxFlash Point, ° C. >700  60 Min Pour Point, ° C. <24  30 MaxCompatibility, Spot# 1 Not required Vanadium, wppm 75 20 350 MaxAluminum + Silicon, wppm 109 6  60 Max Ash, wt % 0.16 0.01  0.1 MaxTotal Sed, Potential, wt % <0.01  0.1 Max Sodium, wppm 78 11 100 Max

Example 6: Improving the Yield and Quality of Coker Products byPre-Treating the Coker Feed with Sodium

Four feedstocks from Table 1, vacuum residuum, SDA tar, visbreakerresidue and Hydrocracker residue, were treated with sodium metal todemonstrate the improved yield and quality of coker products whenpre-treating the coker feedstock with sodium metal prior to thermalconversion, 700 g of the hydrocarbon feedstock was treated with anappropriate mass of sodium in a 1.8 L Parr continuously stirred tankreactor using a batch or semi-batch system under the followingconditions to yield a mixture of converted hydrocarbon and sodium salts.The reaction conditions, feed and product properties are shown inTable 1. The product yield and quality of the coker products areestimated using accepted industry correlations (Gary, J. H., andHandwerk, G. E. (2001). “Petroleum Refining.” Marcel Dekker, New York)for both the ‘as received’ hydrocarbon feedstock and the convertedfeedstock after sodium treatment. The coker products are summarized inTable 6.

The results from Table 6 clearly indicate that when compared to thethermal conversion of the as-received feedstock, treatment the feed withmolten sodium metal prior to thermal conversion increases the totalliquid yield, reduces the coke yield, increases the proportion ofpurified product to residual product and reduces the sulfur content ofall coker products.

Additionally, the results demonstrate how treating a feedstock withmolten sodium metal can unload sulfur recovery processes (i.e., Claus orSCOT plants). In the 4 examples, the sulfur to gas processing (as H₂S)is reduced by over 90%. This process configuration is advantageous toincrease the sulfur handling capacity for a refining facility withoutincreasing sulfur emissions or exceeding limits.

TABLE 6 Vacuum Residual SDA Tar Visbreaker Residue Hydrocracker ResidueH/C Conv. % H/C Conv. % H/C Conv. % H/C Conv. % Feed Feed Change FeedFeed Change Feed Feed Change Feed Feed Change Total Liquid Yield wt %31.16 43.37  39% 42.84 58.19  36% 60.81 66.39  9% 46.68 58.54  25% offeed Coke production wt % 56.00 44.80 −20% 45.28 31.20 −31% 28.80 23.68−18% 41.76 30.88 −26% of feed Sulphur to gas wt % 1.01 0.08 −92% 1.500.12 −92% 0.1 0.01 −84% 1.1 0.09 −92% processing of feed Proportion ofLiquid wt/wt 0.56 0.97  74% 0.95 1.87  97% 2.11 2.80  33% 1.12 1.90  70%Products/Residual Product

Example 7: Producing a High Purity Premium Grade Anode Coke or NeedleCoke by Pretreating with Sodium

The coke product qualities for the same four feedstocks from Example 6,vacuum residuum, SDA tar, visbreaker residue and Hydrocracker residue,is estimated using accepted industry correlations (Gary, J. H., andHandwerk, G. E. (2001). “Petroleum Refining.” Marcel Dekker, New York)for both the ‘as received’ hydrocarbon feedstock and the convertedfeedstock after sodium treatment and are summarized in Table 7. None ofthe cokes produced from the as-received feed meet anode grade cokespecifications, whereas all coke products produced from the convertedfeedstocks are near or exceed the anode grade coke specifications. Thevanadium specification can be achieved by slightly increasing the molarequivalent of sodium in the sodium contacting step.

TABLE 7 Sulfur Vanadium wt % ppm Anode Coke Spec 0.5 150 Vacuum ResidualHydrocarbon Feed 1.79 261 Converted Feed 0.17 122 SDA Tar HydrocarbonFeed 3.31 442 Converted Feed 0.38 167 Visbreaker Residue HydrocarbonFeed 2.06 139 Converted Feed 0.38 31 Hydrocracker Residue HydrocarbonFeed 2.70 460 Converted Feed 0.30 162

Example 8: Improving the Distillation Properties of Petroleum Productsby Pre-Treating the Feed with Sodium

A comparison was made of distillation properties for hydrocarbonfeedstocks before and after treatment with sodium in accordance with theprocedure of Example 1. The results in Table 8 show improved properties,with a reduction in the residue fraction of 1-10% and associatedincreases in the higher-value distillate and gasoil fractions of 0.5-3%and 0.5-8% respectively. This improved product profile provides highervalue products from a given volume of feed, e.g., when conductingdistillations after desulfurization using sodium.

TABLE 8 Diluted DSU DSU DSU Heavy DSU Vacuum DSU VR product Conventionalproduct Bitumen product bottoms product residue product Fraction Naphtha(C5-177) 0 0 1.60 0.65 1.79 0.64 0 0.36 0.00 0 Distillate (177-343)22.27 23.14 20.11 21.28 16.45 19.17 12.39 14.95 0.00 2.62 Gas Oil(343-524) 20.52 21.05 34.09 36.52 29.79 37.42 37.61 39.04 12.66 17.59Resid (524+) 57.21 55.81 44.20 41.56 51.97 42.77 50.00 45.65 87.34 79.80Deltas Naphtha (C5-177) 0 −0.95 −1.15 0.36 0 Distillate (177-343) 0.871.17 2.72 2.56 2.62 Gas Oil (343-524) 0.53 2.42 7.63 1.43 4.93

EQUIVALENTS

While certain embodiments have been illustrated and described, a personwith ordinary skill in the art, after reading the foregoingspecification, can affect changes, substitutions of equivalents andother types of alterations to the processes of the present technologyand products thereof as set forth herein. Each aspect and embodimentdescribed above can also have included or incorporated therewith suchvariations or aspects as disclosed in regard to any or all of the otheraspects and embodiments.

The present technology is also not to be limited in terms of theparticular aspects described herein, which are intended as singleillustrations of individual aspects of the present technology. Manymodifications and variations of this present technology can be madewithout departing from its spirit and scope, as will be apparent tothose skilled in the art. Functionally equivalent methods within thescope of the present technology, in addition to those enumerated herein,will be apparent to those skilled in the art from the foregoingdescriptions. Such modifications and variations are intended to fallwithin the scope of the appended claims. It is to be understood thatthis present technology is not limited to particular methods,feedstocks, compositions, or conditions, which can, of course, vary. Itis also to be understood that the terminology used herein is for thepurpose of describing particular aspects only, and is not intended to belimiting. Thus, it is intended that the specification be considered asexemplary only with the breadth, scope and spirit of the presenttechnology indicated only by the appended claims, definitions thereinand any equivalents thereof.

The embodiments, illustratively described herein may suitably bepracticed in the absence of any element or elements, limitation orlimitations, not specifically disclosed herein. Thus, for example, theterms “comprising,” “including,” “containing,” etc. shall be readexpansively and without limitation. Additionally, the terms andexpressions employed herein have been used as terms of description andnot of limitation, and there is no intention in the use of such termsand expressions of excluding any equivalents of the features shown anddescribed or portions thereof, but it is recognized that variousmodifications are possible within the scope of the claimed technology.Likewise, the use of the terms “comprising,” “including,” “containing,”etc. shall be understood to disclose embodiments using the terms“consisting essentially of” and “consisting of.” The phrase “consistingessentially of” will be understood to include those elementsspecifically recited and those additional elements that do notmaterially affect the basic and novel characteristics of the claimedtechnology. The phrase “consisting of” excludes any element notspecified.

In addition, where features or aspects of the disclosure are describedin terms of Markush groups, those skilled in the art will recognize thatthe disclosure is also thereby described in terms of any individualmember or subgroup of members of the Markush group. Each of the narrowerspecies and subgeneric groupings falling within the generic disclosurealso form part of the invention. This includes the generic descriptionof the invention with a proviso or negative limitation removing anysubject matter from the genus, regardless of whether or not the excisedmaterial is specifically recited herein.

As will be understood by one skilled in the art, for any and allpurposes, particularly in terms of providing a written description, allranges disclosed herein also encompass any and all possible subrangesand combinations of subranges thereof. Any listed range can be easilyrecognized as sufficiently describing and enabling the same range beingbroken down into at least equal halves, thirds, quarters, fifths,tenths, etc. As a non-limiting example, each range discussed herein canbe readily broken down into a lower third, middle third and upper third,etc. As will also be understood by one skilled in the art all languagesuch as “up to,” “at least,” “greater than,” “less than,” and the like,include the number recited and refer to ranges which can be subsequentlybroken down into subranges as discussed above. Finally, as will beunderstood by one skilled in the art, a range includes each individualmember.

All publications, patent applications, issued patents, and otherdocuments (for example, journals, articles and/or textbooks) referred toin this specification are herein incorporated by reference as if eachindividual publication, patent application, issued patent, or otherdocument was specifically and individually indicated to be incorporatedby reference in its entirety. Definitions that are contained in textincorporated by reference are excluded to the extent that theycontradict definitions in this disclosure.

Other embodiments are set forth in the following claims, along with thefull scope of equivalents to which such claims are entitled.

What is claimed is:
 1. A process for improving the yield of liquidhydrocarbons from a thermal conversion process comprising: contacting ahydrocarbon feedstock with an effective amount of sodium metal and aneffective amount of exogenous capping agent at a temperature of 250-500°C., to produce a mixture of sodium salts and a converted feedstock,wherein the hydrocarbon feedstock comprises hydrocarbons with a sulfurcontent of at least 0.5 wt %, an asphaltene content of at least 1 wt %and micro carbon residue content of at least 5 wt %; the convertedfeedstock comprises hydrocarbons with a sulfur content less than that inthe hydrocarbon feedstock, a micro carbon residue content less than thatin the hydrocarbon feedstock and an asphaltene content less than that inthe hydrocarbon feedstock; and subjecting the converted feedstock to athermal conversion process to produce a gaseous product, a purifiedproduct and a residual product, wherein the proportion of purifiedproduct to residual product is greater than that produced by subjectingthe hydrocarbon feedstock in the same thermal conversion process.
 2. Aprocess comprising: contacting a hydrocarbon feedstock with an effectiveamount of sodium metal and an effective amount of exogenous cappingagent at a temperature of 250-500° C., to produce a mixture of sodiumsalts and a converted feedstock, wherein the hydrocarbon feedstockcomprises hydrocarbons with a sulfur content of at least 0.5 wt %, anasphaltene content of at least 1 wt %, a vanadium content of at least 15ppm and a micro carbon residue content of at least 5 wt %; the convertedfeedstock comprises hydrocarbons with a sulfur content less than that inthe hydrocarbon feedstock, micro carbon residue less than that in thehydrocarbon feedstock and an asphaltene content less than that in thehydrocarbon feedstock; and subjecting the converted feedstock to athermal conversion process to produce a premium anode grade coke productwith less than 0.5% wt % sulfur and less than 150 ppm vanadium.
 3. Aprocess comprising: contacting a hydrocarbon feedstock with an effectiveamount of sodium metal and an effective amount of exogenous cappingagent at a temperature of 250° C.-500° C., to produce a mixture ofsodium salts and a converted feedstock, wherein the hydrocarbonfeedstock comprises hydrocarbons with a sulfur content of at least 0.5wt %, an asphaltene content of at least 1 wt %, a nickel content of atleast 10 ppm and a micro carbon residue content of at least 5 wt %; theconverted feedstock comprises hydrocarbons with a sulfur content lessthan 0.5 wt %, micro carbon residue less than that in the hydrocarbonfeedstock and an asphaltene content less than 0.25 wt % and an ashcontent <0.1 wt %; and treating the converted feedstock in a thermalconversion process to produce a high purity needle coke product withless than 0.5 wt % sulfur, less than 0.7 wt % nitrogen, less than 10 ppmnickel, a coefficient of thermal expansion greater than 2.5×10⁷/° C. andan electrical resistivity of 320×10⁶ Ohm-In.
 4. A process comprising:contacting a hydrocarbon feedstock with an effective amount of sodiummetal and an effective amount of exogenous capping agent at atemperature of 250° C.-500° C., to produce a mixture of sodium salts anda converted feedstock, wherein the hydrocarbon feedstock compriseshydrocarbons with a sulfur content of at least 0.5 wt %, an asphaltenecontent of at least 1 wt % and a total metal content of at least 100ppm; the converted feedstock comprises hydrocarbons having a sulfurcontent less than 0.5 wt %, a vanadium content less than 50 ppm, anickel content less than 50 ppm, a lower concentration of asphaltenesthan that in the hydrocarbon feedstock, and a greater proportion oflower boiling point hydrocarbons (<538° C.) to residual hydrocarbons(>538° C.) than that in the hydrocarbon feedstock; optionally furthersubjecting the converted feedstock to a thermal conversion process toprovide a double-converted product; and subjecting the convertedfeedstock or double-converted feedstock to a catalytic conversionprocess to produce a fuel grade product without blending or furtherconversion processing.
 5. A process comprising: contacting a hydrocarbonfeedstock with an effective amount of sodium metal and an effectiveamount of exogenous capping agent at a temperature of 250° C.-500° C.,to produce a mixture of sodium salts and a converted feedstock, whereinthe hydrocarbon feedstock comprises hydrocarbons with a sulfur contentof at least 0.5 wt %, an asphaltene content of at least 1 wt % and failsto meet one or more fuel-grade specifications selected from the groupconsisting of viscosity, density, micro carbon residue, metals contentand cleanliness/compatibility; the converted product comprises ahydrocarbon having a sulfur content less than 0.5 wt %, and meets one ormore fuel grade specifications selected from the group consisting ofviscosity, density, micro carbon residue, metals content andcompatibility; and the fuel-grade specifications are viscosity of lessthan 380 cSt @ 50 C, a density of less than 991 kg/m³, a micro carbonresidue content less than 18 wt %, a vanadium content less than 350mg/kg and a cleanliness spot test result of 1 or 2 as measured by ASTMD4740.
 6. The process of claim 4 further comprising subjecting theconverted feedstock to a thermal conversion process to provide thedouble-converted feedstock as and a solid coke product, wherein theconverted feedstock has a microcarbon residue content of at least 5 wt%, and the double-converted product comprises a hydrocarbon having alower concentration of impurities than that in the hydrocarbonfeedstock, and a proportion of lower boiling point hydrocarbons (<538°C.) to higher boiling point residuum hydrocarbons (>538° C.) greaterthan that of the converted feedstock.
 7. The process of any one ofclaims 1-6, further comprising pretreating the hydrocarbon feedstockbefore the contacting step to provide a purified feedstock and apretreated hydrocarbon feedstock, wherein the purified feedstockcomprises a lower concentration of impurities than the hydrocarbonfeedstock before pretreatment, the pretreated hydrocarbon feedstockcomprises a higher concentration of impurities than the purifiedfeedstock, and the pretreated hydrocarbon feedstock is the feedstocksubjected to the contacting step to produce the converted feedstock. 8.The process of claim 7, wherein the pretreatment step comprises phaseseparation by an externally applied field, separation by addition ofheat, hydroconversion, thermal conversion, catalytic conversion,catalytic treatment, solvent extraction, solvent deasphalting or acombination of any two or more thereof.
 9. The process of claim 7 orclaim 8, wherein the pretreatment step further comprises contacting thehydrocarbon feedstock with exogenous hydrogen and/or a catalyst toremove one or more of sulfur, nitrogen, oxygen, metals and asphaltenes.10. The process of any one of claims 1-9, wherein the thermal conversionprocess comprises visbreaking, delayed coking, fluid coking,Flexicoking™, pyrolysis, a variant thereof or a combination of any twoor more thereof.
 11. The process of claim 10 wherein the thermalconversion process is operated at a temperature of about 400° C. toabout 570° C.
 12. The process of claim 10 or claim 11 wherein thethermal conversion process is operated at a pressure of about 10 toabout 200 psig.
 13. The process of any one of claims 1-12 wherein thethermal conversion process is operated at about 450° C. to about 500° C.and at about 20-100 psig.
 14. The process of claim 4 wherein thecatalytic conversion process comprises fluid catalytic cracking (FCC),residual FCC, hydrotreating, residual hydrotreating, hydrocracking,catalytic reforming, hydrodesulfurization, hydrodenitrogenation,hydrodemetallation, or residue upgrading/hydroconversion, their variantsor a combination of any two or more thereof.
 15. The process of claim 14wherein the catalyst comprises cobalt, molybdenum, nickel, tungsten,platinum, palladium, alumina, silica, zeolites, their isomers, oxides,sulfides or combinations of any two or more thereof.
 16. The process ofclaim 15 wherein the catalytic conversion process is operated at atemperature from about 250° C. to about 575° C.
 17. The process of claim15 wherein the catalytic conversion process is operated at a pressure ofabout 10 to about 3000 psig.
 18. The process of any one of claims 4 or6-17 wherein the catalytic conversion process is operated at about 400°C. to about 575° C. and at about 1000 to about 3000 psig.
 19. Theprocess of any one of claims 4 or 6-17 wherein the catalytic conversionprocess is operated at about 450° C. to about 575° C. and at about 15 toabout 100 psig.
 20. The process of any of any one of claims 1 to 19further comprising recovering hydrogen sulfide using a sulfur recoveryunit in conjunction with the thermal or catalytic conversion step,wherein the capacity of the sulfur recovery unit is increasedproportionately to the sulfur converted to sodium salts during treatmentwith sodium.
 21. The process of any one of claims 1-20, wherein thehydrocarbon feedstock is or is derived from a virgin crude oil or aproduct of a thermal cracking process.
 22. The process of any one ofclaims 1-20, wherein the hydrocarbon feedstock is selected from thegroup consisting of petroleum, heavy oil, bitumen, shale oil, and oilshale.
 23. The process of any one of claims 1-22, wherein the sulfurcontent ranges from 0.5 wt % to 15 wt %.
 24. The process of any one ofclaims 1-23, wherein the asphaltene content ranges from 1 wt % to 100 wt%.
 25. The process of claim 24, wherein the asphaltene content rangesfrom 2 wt % to 40 wt %.
 26. The process of any one of claims 1-25wherein the hydrocarbon feedstock comprises one or more of refineryintermediate streams, hydrocracker residue, hydroprocessing residue, FCCslurry, residual FCC slurry, atmospheric or vacuum residuums, solventdeasphalting tar, deasphalted oil, visbreaker tar, high sulfur fuel oil,low sulfur fuel oil, asphaltenes, asphalt, steam cracked tar, LC-Fining®residue, or H-Oil® residue.
 27. The process of any one of claims 1-26,wherein the hydrocarbon feedstock has a viscosity from 1 to 10,000,000cSt at 50° C. and a density of 800 to 1200 kg/m³ at 15.6° C.
 28. Theprocess of claim 1-27, wherein the hydrocarbon feedstock has a viscosityfrom 400 to 9,000,000 cSt at 50° C.
 29. The process of any one of claims1-28 wherein the hydrocarbon feedstock is a solid at room temperature30. The process of any one of claims 1-29, wherein the sulfur contentcomprise asphaltenic sulfur and non-asphaltenic sulfur, and theproportion of asphaltenic sulfur to non-asphaltenic sulfur in theconverted feedstock is lower than in the hydrocarbon feedstock.
 31. Theprocess of any one of claims 1-30 wherein the viscosity of the convertedfeedstock is reduced by at least 50 cSt at 50° C. or 40% and the densityof the converted feedstock is reduced by about 5 to about 25 kg/m³ perwt % of the reduction in sulfur content of the converted feedstockcompared to the hydrocarbon feedstock.
 32. The process of any one ofclaims 1-31 wherein the iron and vanadium content of the convertedfeedstock have been reduced by at least 40% compared to the hydrocarbonfeedstock.
 33. The process of any one of claims 1-32 wherein the nickelcontent of the converted feedstock has been reduced by at least 40%compared to the hydrocarbon feedstock.
 34. The process of any one ofclaims 1-33 wherein at least 40% of the asphaltene content in thehydrocarbon feedstock is converted to a liquid hydrocarbon oil in theconverted feedstock.
 35. The process of any preceding claim wherein theexogenous capping agent is hydrogen, hydrogen sulfide, natural gas,methane, ethane, propane, butane, pentane, ethene, propene, butene,pentene, dienes, isomers of the forgoing, or a mixture of any two ormore thereof.
 36. The process of any preceding claim wherein thehydrocarbon feedstock is combined with sodium metal at a pressure ofabout 400 psig to about 3000 psig
 37. The process of any preceding claimwherein the reaction of hydrocarbon feedstock with sodium metal occursfor a time from 1 minute to 120 minutes.
 38. The process of anypreceding claim further comprising separating the sodium salts from theconverted feedstock.
 39. The process of claim 38 wherein the separatingcomprises a. heating the mixture of sodium salts and converted feedstockwith elemental sulfur to a temperature from about 150° C. to 500° C. toprovide a sulfur-treated mixture comprising agglomerated sodium salts;and b. separating the agglomerated sodium salts from the sulfur treatedmixture, to provide a desulfurized liquid hydrocarbon and separatedsodium salts.
 40. The process of claim 39 further comprisingelectrolyzing the separated sodium salts to provide sodium metal andelemental sulfur.
 41. The process of any preceding claim, wherein thesodium salts comprise one or more of sodium sulfide, sodiumhydrosulfide, or sodium polysulfide.
 42. The process of claim 40 orclaim 41, wherein the electrolyzing is carried out in an electrochemicalcell comprising an anolyte compartment, a catholyte compartment, aNaSICON membrane that separates the anolyte compartment from thecatholyte compartment, wherein a cathode comprising sodium metal isdisposed in a catholyte in the catholyte compartment, an anodecomprising the sodium salts are disposed in anolyte in the anolytecompartment, and an electrical power supply is electrically connected tothe anode and cathode.